Electronic assemblies are used in a vast assortment of equipment including computers and communication systems. An electronic assembly typically comprises two or more components bonded together in a laminate structure with a layer of adhesive or solder material. The components of the assembly commonly include a circuit board and a heat sink. The layer of adhesive is usually of a thermally conductive material. Heat generated by various circuit components mounted on the circuit board is drawn away from the board by the heat sink.
The components of the assembly typically have different coefficients of thermal expansion (contraction). This undesirably causes thermally induced interfacial shearing and peeling stresses when the assembly is heated and cooled. These stresses are greatest at the perimeter of the assembly. Consequently, delamination often occurs at the perimeter typically leading to reduced performance or failure. Therefore, electronic assemblies having improved resistance to delamination are needed.